


Big Red

by ACatWhoWrites



Series: #BoKuroo Week 2019 [1]
Category: Haikyuu!!
Genre: Alternate Universe, Alternate Universe - Demons, Alternate Universe - Hellboy Fusion, Alternate Universe - Supernatural Elements, BoKuroo Week, BuKuroo Week 2019, Gen
Language: English
Status: Completed
Published: 2019-04-05
Updated: 2019-04-05
Packaged: 2020-01-05 00:55:36
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,038
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18355286
Author URL: https://archiveofourown.org/users/ACatWhoWrites/pseuds/ACatWhoWrites
Summary: Bokuto didn't realize the big plan to fight bad guys was assigning him a partner who's not entirely human, but it's cool.





	Big Red

**Author's Note:**

> day one - supernatural

Not that he’ll admit it, but being so far underground is kind of starting to rattle Bokuto’s cage. He likes fresh air and clouds. They can’t contain his enthusiasm and imagination. All of these many hundreds of feet beneath what could be a crushing force of earth really dampen his mood and makes his skin feel like insects are crawling underneath.

Flicking a spider away, he smiles at the silent, blond lab assistant and steps into the door opened for him.

“The doctor will be with you shortly,” he says tonelessly.

“Wait—You’re not staying with me?”

The assistant sneers. “Someone of your status and experience couldn’t be _afraid_ , could he? No worries. He doesn’t bite.”

The door shuts, and Bokuto wonders if he’s been insulted. He _isn’t_ afraid of being alone; he doesn’t like the idea of being alone in a strange place so far underground where he’d never be found.

“Don’t mind him,” a low voice purrs. “He’s really not that bad, and I don’t usually bite.”

Hidden by some apparatus Bokuto recognizes as exercise equipment, a red-skinned body lifts itself from the floor to stand at a height that rivals his own. They’re male and muscular, but rather than a prime physique or incredibly disastrous bedhead, Bokuto focuses on the two protuberant stumps on either temple.

“Hellboy.”

He bows, smiling rather cattily. “A pleasure, Kotaro Bokuto-san, but call me Kuroo.”

“Being called a demon isn’t always a compliment, even to a demon-born child.” Bokuto squawks and raises his arms, facing another lab coat who is clearly unimpressed. “Doctor Keiji Akaashi,” he offers a bow, “thank you for coming all this way.” He casts an eye towards Kuroo and hisses, “Put some clothes on.”

Bokuto likes to think he recovers well and smiles broadly. “No problem! I heard there was an idea to take down some B.B.G.s, and that’s what I live for.”

“B.B.G.s?”

“Big Bad Guys,” Bokuto replies. He says it like it’s obvious, but few people can keep up with his acronyms.

“You’re accomplished on your own,” Kuroo comments. His T-shirt gets caught on his horns. The scientist sighs and yanks it down into place. “Are you sure you can share the spotlight?”

“I’ve never tried!” he claims brightly. “I’m sure it won’t matter. As long as I’m seen as awesome, I’ll be okay.” He flashes a thumbs up.

Akaashi raises a tablet to get their attention. “Since no one seems to have told you, Bokuto-san, the idea is to place Kuroo-san into your care.”

“What—”

“There should be no risk to yourself or your home. We’ll be affording you an allowance for him.” He swipes the screen and pulls the image from the tablet, sending it into the middle of the room. Statistics, images, and video all show Kuroo from apparently all stages of life, in combat, training, and rest. “He is half-human, half-demon. His demonic heritage is aided by extensive physical training, granting immense strength and stamina. Virtually immune to disease and injury, he also has a rapid healing ability. If you come across any unusual texts, he can comprehend most ancient languages.

“If you can withstand is awful sense of humor and motivate his lazy ass, you should get along well and take down lots of ‘B.B.G.s’.” The air clears, and Bokuto blinks at the afterimages.

“So...wait. I’m like his foster parent?”

Akaashi nods impassively. “If you want to think of it that way.”

Bokuto purses his lips and bounces his head. Okay, then. He’s a parent in his tender twenties.

“You may leave immediately.”

“Aw, Akaashi, after all we’ve been through, can’t you be a little kinder?”

“No. You’ve aged me, Kuroo-san.” He swipes his finger in patterns over the face of the tablet, but Bokuto can’t see that it’s even on. “Return when you require ammunition or information, and we’ll fulfil any requests.” Bokuto sees Kuroo smile, and the half-human ambles to some open doors. A bedroom.

Bokuto follows after silently pointing after him and getting permission from Akaashi. Kuroo has a large duffel on his bed. His tail wags slowly behind him as he packs. Along with predominantly black and various shades of red clothing, there are grenades, packages labelled with names of herbs Bokuto recognizes, relics, and a handgun closer to the size of a sawed-off shotgun. 

“So. How old are you, Kuroo?” Closer, he thinks he smells roasted peanuts. Maybe it’s a favorite snack of the half-human.

“Seventy-five this November.”

Bokuto trips over his feet but catches himself. _Seventy-five_? That’s older than his grandparents! “You look really good for your age.”

“Thank you. We like to think of it as reverse dog years, because nothing else makes sense.” He slings the duffel over his shoulder. “Shall we, Dad?”

The outer room is empty. Kuroo pauses for a moment and looks around, perhaps a little wistful.

The same blond assistant is waiting for them in the hall. “I’ll take you up,” he says.

“Gonna miss me, Tsukki?”

“Absolutely not. The farther away you are, the less mess we have to clean up.”

“Oh, come on, kiddo. It’s been fun!”

“‘Fun’ is not the word I would use.”

“ _I_ think it’s been fun, and I’m going to miss you, kiddo.”

The assistant _tsk_ s and scowls. It doesn’t look as irritated as he sounds, though, and he responds to Kuroo’s banter on the elevator ride topside.

Bokuto barely resists the urge to run outside and roll on the grass once they’re escorted outside. Kuroo catches the assistant and ruffles his curls. The younger man doesn’t step foot outside the building. It’s strange.

His phone pings, and there’s a message from his bank about transferred funds that make his knees nearly give out.

Kuroo smacks his shoulder and asks, “Whereto first, Dad?”

They’ve got the funds to afford it, now, so Bokuto suggests food. “I actually know of a great grill a couple stops away, although…” He squints at Kuroo. There’s no way they can hide his demonic features. “Just behave, alright? Don’t take out any grenades or guns or whatever while we’re eating.”

The half-human smiles sharply, not at all reassuring. “I’ll do my best to restrain myself.”

**Author's Note:**

> Belated posting, but oh well.
> 
> I'm excited for the new Hellboy movie. I don't know what it is, but I really like the character yet have never read the comics. He felt like a good fit for Kuroo. Similar attitude and black/red aesthetic.


End file.
